Prior art U.S. Pat. No. 4,882,600, issued Nov. 21, 1989, and U.S. Pat. No. Des. 321,704, issued Nov. 19, 1991, each disclose an underwater camera unit comprising a lighttight camera body provided with a depressible shutter release button, and a transparent water-resistant housing enclosing the camera body. The water-resistant housing has a flexible housing section which is located over the shutter release button to be manually deflected to depress the shutter release button. Ordinary finger pressure applied to the flexible housing section is used to manually deflect the flexible housing section. The flexible housing section must be stiff enough to withstand the water pressure at the maximum underwater depth intended for the camera unit, in order to avoid being accidentally deflected to depress the shutter release button. However, increasing the stiffness of the flexible housing section can make it difficult to manually deflect using finger pressure, when the camera unit is above-water.